Ch.15 Transmitter Systems Exam Questions

Chapter 15: Transmitter Synthesis, Storage, Transport, and Inactivation

Test Bank

Type: multiple choice question

Title: Chapter 15 Question 01

1. Unlike low-molecular-weight transmitters, neuropeptides are synthesized in

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how low-molecular-weight transmitters and neuropeptides differ in their synthesis, storage, and release.

Bloom’s Level: 1. Remembering

a. the cell body and packaged in dense-core vesicles for transport.

b. the axon terminals and not packaged into vesicles.

c. the cell body and not packaged into vesicles.

d. dendrites and somatic varicosities and packaged into small synaptic vesicles for transport.

e. the axon terminals and packaged in dense-core vesicles.

Type: multiple choice question

Title: Chapter 15 Question 02

2. Nictric oxide, carbon monoxide, and endocannabinoids are unusual among molecular messengers in that they are

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how low-molecular-weight transmitters and neuropeptides differ in their synthesis, storage, and release.

Bloom’s Level: 2. Understanding

a. not synthesized by the body but are ingested directly.

b. synthesized in terminals but are not packaged into vesicles.

c. synthesized in the cell body rather than in axon terminals.

d. packaged in dense-core vesicles rather than synaptic vesicles.

e. packaged into vesicles containing multiple messengers.

Type: multiple choice question

Title: Chapter 15 Question 03

3. Compared with the synthesis of low-molecular-weight neurotransmitters, the synthesis of peptides

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how low-molecular-weight transmitters and neuropeptides differ in their synthesis, storage, and release.

Bloom’s Level: 2. Understanding

a. is faster and more efficient.

b. occurs nearer to release sites.

c. occurs inside of vesicles.

d. is slower and quantities are more limited.

e. does not involve enzymes.

Type: multiple choice question

Title: Chapter 15 Question 04

4. Unlike low-molecular-weight neurotransmitters, peptides are synthesized

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how low-molecular-weight transmitters and neuropeptides differ in their synthesis, storage, and release.

Bloom’s Level: 2. Understanding

a. on ribosomes.

b. inside of vesicles.

c. in the axon terminals.

d. outside of the CNS.

e. in the extracellular space.

Type: multiple choice question

Title: Chapter 15 Question 05

5. If preganglionic neurons are stimulated such that ACh is released from ganglionic neurons at a high level, these neurons become depleted

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 1. Remembering

a. after a few (3-7) seconds of stimulation.

b. after a few (3-7) minutes of stimulation.

c. after about 20-30 minutes of stimulation.

d. in less than an hour.

e. after more than an hour.

Type: multiple choice question

Title: Chapter 15 Question 06

6. ChAT and AChE are

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. two components of ACh receptors.

b. molecules that assist with docking vesicles to the cell membrane.

c. the two molecules from which ACh is synthesized.

d. enzymes responsible for the synthesis and the degradation of ACh.

e. molecules responsible for the packaging of ACh into vesicles.

Type: multiple choice question

Title: Chapter 15 Question 07

7. Acetylcholine is synthesized by _______ and degraded by _______.

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. choline; ChAT

b. AChE; AcCoA

c. HC-3; AChE

d. ChAT; AChE

e. AcCoA; ChAT

Type: multiple choice question

Title: Chapter 15 Question 08

8. The ingredients or precursors required for the synthesis of acetylcholine are sourced from

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. glial cells.

b. the cell body.

c. the extracellular fluid and the mitochondria.

d. they are synthesized in the synaptic terminal.

e. the diet.

Type: multiple choice question

Title: Chapter 15 Question 09

9. If ChAT in the cytoplasm is inhibited, the predicted effect would be

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 4. Analyzing

a. an accumulation of high levels of ACh.

b. a depletion in ACh levels.

c. the release of excessive levels of ACh from the synapse.

d. an accumulation of ACh outside of vesicles, but a decrease in ACh-packed vesicles.

e. an inability of vesicles containing ACh to fuse with the synaptic membrane.

Type: multiple choice question

Title: Chapter 15 Question 10

10. The accumulation of ACh levels in a synaptic terminal is limited or reduced by increasing activity of

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 4. Analyzing

a. ATP.

b. AcCoA.

c. AChE.

d. VAChT.

e. ChAT.

Type: multiple choice question

Title: Chapter 15 Question 11

11. Identification of the rate-limiting step in the synthesis of norepinephrine was achieved by measuring the

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. activity of dopamine β-hydroxylase in the presence of varying levels of dopamine.

b. amount of DOPA produced after inhibition of tyrosine hydroxylase.

c. amount of each relevant enzyme in the cytoplasm.

d. amount of norepinephrine produced when the preparation was bathed in various precursors.

e. amount of norepinephrine produced when various enzymes were inhibited.

Type: multiple choice question

Title: Chapter 15 Question 12

12. Compared to other neurotransmitters, serotonin synthesis is especially dependent on the levels of precursors made available through

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. reuptake.

b. mitochondria.

c. the diet.

d. hydrolyzation.

e. synthesis in the cell body.

Type: multiple choice question

Title: Chapter 15 Question 13

13. GABA is synthesized from

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. glutamate by the enzyme GAD.

b. GAD by the enzyme α-ketoglutarate.

c. glutamic acid by the enzyme decarboxylase.

d. ATP by the enzyme GABA hydroxylase.

e. GAD by the enzyme adenosine triphosphate.

Type: multiple choice question

Title: Chapter 15 Question 14

14. An experimental increase in the availability of glutamic acid decarboxylase (GAD) would be expected to produce a(n)

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 4. Analyzing

a. increase in GABA.

b. reduction in GABA.

c. increase in glutamate.

d. increase in glutamine.

e. reduction in glutamine.

Type: multiple choice question

Title: Chapter 15 Question 15

15. In the synthesis cycle of glutamate, an increase in the activity of glutaminase would be predicted to lead to a(n)

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. increase in glutamate and a reduction in glutamine.

b. increase in glutamine and a reduction in glutamate.

c. increase in both glutamine and glutamate.

d. reduction in both glutamine and glutamate.

e. reduction in glutamate and no change in glutamine.

Type: multiple choice question

Title: Chapter 15 Question 16

16. In the synthesis cycle of glutamate, it is generally the case that

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

a. neurons convert glutamate to glutamine, while glial cells convert glutamine to glutamate.

b. neurons convert glutamine to glutamate, while glial cells convert glutamate to glutamine.

c. neurons convert glutamine to glutamate, which is then hydrolyzed by glutaminase in the synaptic cleft.

d. glial cells convert glutamine to glutamate which is then recycled into the presynaptic neuron through reuptake.

e. glial cells convert glutamine to glutamate, which is then hydrolyzed by GAD before diffusing away.

Type: multiple choice question

Title: Chapter 15 Question 17

17. Imagine a hypothetical pathway in which precursor X and precursor Y are combined by enzyme Z in order to produce neurotransmitter XYZ. Which of the choices below would represent feedback inhibition?

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 3. Applying

a. Increasing levels of X or of Y lead to a reduction in activity of enzyme Z.

b. Increasing levels of enzyme Z lead to an increase in levels of XYZ.

c. Increasing levels of enzyme Z lead to a reduction in availability of X and Y.

d. Increasing levels of XYZ lead to an increase in the availability of X.

e. Increasing levels of XYZ lead to a reduction in the activity of enzyme Z.

Type: multiple choice question

Title: Chapter 15 Question 18

18. Imagine a hypothetical pathway in which precursor X and precursor Y are combined by enzyme Z in order to produce neurotransmitter XYZ. You observe that as levels of XYZ increase in the cytoplasm, the activity of enzyme Z slows down. This is an example of

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 3. Applying

a. positive feedback.

b. feedback inhibition.

c. retrograde transport.

d. anterograde synthesis.

e. a rate limiting step.

Type: multiple choice question

Title: Chapter 15 Question 19

19. Which of these correctly represents the sequence of norepinephrine synthesis?

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 1. Remembering

a. AAD, dopamine, epinephrine, norepinephrine

b. DOPAC, dopamine, norepinephrine

c. Tyrosine, dopamine, epinephrine, norepinephrine

d. DOPA, epinephrine, norepinephrine

e. Tyrosine, DOPA, dopamine, norepinephrine

Type: multiple choice question

Title: Chapter 15 Question 20

20. Feedback inhibition can be observed in the synthesis of norepinephrine through the

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 2. Understanding

a. inhibition of tyrosine hydroxylase by norepinephrine.

b. degradation of dopamine by DOPAC.

c. availability of dopamine β-hydroxylase.

d. inhibition of AAAD by DOPA.

e. synthesis of norepinephrine by dopamine β-hydroxylase.

Type: multiple choice question

Title: Chapter 15 Question 21

21. Imagine that a hypothetical neurotransmitter, neurotran-X (NTX), is synthesized from two ingredients, neuro-A and tran-B. An enzyme, neurotranoxylase (NTO), is responsible for producing neurotran-X from the two ingredients. If the rate of synthesis of NTX is controlled through feedback inhibition, you would expect to observe experimentally

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 4. Analyzing

a. increasing levels of NTO will lead to increased levels of NTX.

b. reducing levels of neuro-A will reduce levels of NTX.

c. increasing levels of NTX will lead to reduced activity of NTO.

d. reducing levels of neuro-A will lead to reduced activity of NTO.

e. reducing levels of NTX will lead to reduced activity of NTO.

Type: multiple choice question

Title: Chapter 15 Question 22

22. Scientists are attempting to characterize a novel neurotransmitter, neurotran-Y (NTY), which is synthesized by the enzyme neuro-y-oxidase (NYO) from a precursor, neuro-A. In an experiment they inject artificially high levels of NTY into the pre-synaptic terminal of a cell that releases NTY. Shortly thereafter, they measure the activity of NYO and observe that its activity has been suppressed. The scientists have found evidence for

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 4. Analyzing

a. reuptake.

b. hydrolyzation.

c. co-transmission.

d. feedback inhibition.

e. fast axonal transport.

Type: multiple choice question

Title: Chapter 15 Question 23

23. When animals are subjected to stress, prolonged activation of the sympathetic nervous system results in a(n)

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Describe the difference between short-term and long-term regulation of transmitter synthesis.

Bloom’s Level: 2. Understanding

a. increase in production of enzymes that degrade neurotransmitters, such as MAO.

b. reduction in the numbers of enzymes that degrade neurotransmitters, such as ADH.

c. increase in production of enzymes used for neurotransmitter synthesis, such as TH.

d. increase in the numbers of enzymes used for neurotransmitter synthesis, such as ATPase.

e. increase in the availability of precursors such as tryptophan.

Type: multiple choice question

Title: Chapter 15 Question 24

24. Long-term changes to the rate of neurotransmitter synthesis can be observed in response to

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Describe the difference between short-term and long-term regulation of transmitter synthesis.

Bloom’s Level: 2. Understanding

a. prolonged activation of the sympathetic nervous system due to stress.

b. availability of the neurotransmitter in the synaptic terminal.

c. availability of the neurotransmitter in the extracellular space.

d. chronic changes to glutamine availability in the diet.

e. changes in the composition of gut microbiota.

Type: multiple choice question

Title: Chapter 15 Question 25

25. One of the mechanisms through which long-term changes to the rate of neurotransmitter synthesis are achieved is

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Describe the difference between short-term and long-term regulation of transmitter synthesis.

Bloom’s Level: 2. Understanding

a. the production of new receptors for neurotransmitter reuptake.

b. the synthesis of new enzymes involved in neurotransmitter production.

c. the production of g-protein coupled receptors used for inhibitory feedback.

d. a reduction in the electrical excitability of neurons.

e. an increase the efficiency with which neurotransmitters are packed into vesicles.

Type: multiple choice question

Title: Chapter 15 Question 26

26. Relatively small quantities of neuropeptides are required for signaling, in part because

Feedback: Subhead: Neurotransmitter Synthesis

Learning Objective: Explain why only a few molecules of a peptide are needed to influence a target cell.

Bloom’s Level: 2. Understanding

a. they have a much higher affinity for their receptors than low-molecular-weight transmitters.

b. they are synthesized so quickly that a continuous supply is available.

c. one molecule can typically bind to many receptors at a time.

d. the binding sites are extremely close to the release sites.

e. their metabotropic receptors can amplify the signal through intracellular pathways.

Type: multiple choice question

Title: Chapter 15 Question 27

27. Low-molecular-weight transmitters are packaged in _______, while neuropeptides are packaged in _______.

Feedback: Subhead: Storage of Transmitters in Vesicles

Learning Objective: Describe the difference between vesicles that store low-molecular-weight transmitters and those that store neuropeptides.

Bloom’s Level: 2. Understanding

a. small, dense-core vesicles; large, clear vesicles

b. small, clear vesicles; large, clear vesicles

c. large vesicles in the cell body; small vesicles in the axon terminal

d. large vesicles in the cytoplasm; small vesicles in the soma

e. small, clear vesicles; large, dense-core vesicles

Type: multiple choice question

Title: Chapter 15 Question 28

28. The functions of proteins such as VAChTs, VGLUT1, and VIAAT is to

Feedback: Subhead: Storage of Transmitters in Vesicles

Learning Objective: Describe the difference between vesicles that store low-molecular-weight transmitters and those that store neuropeptides.

Bloom’s Level: 2. Understanding

a. degrade neurotransmitters into simpler molecules.

b. transport vesicles along microtubules.

c. package neurotransmitters into vesicles.

d. synthesize neurotransmitters from precursors.

e. facilitate diffusion away from the synaptic cleft.

Type: multiple choice question

Title: Chapter 15 Question 29

29. One important feature of the transport proteins used to package neurotransmitters into vesicles is that

Feedback: Subhead: Storage of Transmitters in Vesicles

Learning Objective: Explain how the accumulation of transmitter in vesicles is mediated.

Bloom’s Level: 2. Understanding

a. they often have low specificity and may transport more than one type of neurotransmitter.

b. one type of protein transports the low-molecular-weight transmitters, and a second type transports neuropeptides.

c. they are usually saturated and serve as the rate-limiting factor for the availability of vesicles.

d. they may also be present in the cell membrane and transport neurotransmitters directly into the extracellular space.

e. they are highly efficient so that little neurotransmitter can be found outside of vesicles.

Type: multiple choice question

Title: Chapter 15 Question 30

30. The concentration or quantity of a neurotransmitter in each vesicle

Feedback: Subhead: Storage of Transmitters in Vesicles

Learning Objective: Explain how the accumulation of transmitter in vesicles is mediated.

Bloom’s Level: 2. Understanding

a. is constant across all neurons for a given neurotransmitter.

b. is constant for vesicles using a given transport protein.

c. may vary between neurons, but is constant within a neuron for a given neurotransmitter.

d. may vary based on availability of the transmitter and concentration of chloride ions.

e. may vary based on the availability of enzymes used in synthesis.

Type: multiple choice question

Title: Chapter 15 Question 31

31. Which best illustrates the concept of “co-transmission”?

Feedback: Subhead: Storage of Transmitters in Vesicles

Learning Objective: Explain the concept of co-storage and co-release.

Bloom’s Level: 2. Understanding

a. A single vesicle contains both glycine and GABA, and releases both synchronously

b. A synaptic terminal contains some vesicles with dopamine, and some with norepinephrine, that are released simultaneously

c. A synaptic terminal contains some vesicles with dopamine, and some with norepinephrine, that are released at different times based on different patterns of activity

d. Both a and b

e. a. b. and c

Type: multiple choice question

Title: Chapter 15 Question 32

32. A primary difference between axoplasmic flow and axonal transport is that axonal transport

Feedback: Subhead: Axonal Transport

Learning Objective: Distinguish between axoplasmic flow and axonal transport.

Bloom’s Level: 2. Understanding

a. is much faster than axoplasmic flow.

b. moves from the cell body to the axons.

c. primarily transports structural proteins.

d. is much slower than axoplasmic flow.

e. is difficult to observe through tracing or labeling.

Type: multiple choice question

Title: Chapter 15 Question 33

33. The movement of organelles and proteins toward the axon terminal is called _______ while the movement toward the cell body is called _______.

Feedback: Subhead: Axonal Transport

Learning Objective: Distinguish between axoplasmic flow and axonal transport.

Bloom’s Level: 2. Understanding

a. top-down transport; bottom-up transport

b. anterograde transport; retrograde transport

c. axoplasmic flow; somatoplasmic flow

d. retrograde transport; anterograde transport

e. axonal transport; somatic transport

Type: multiple choice question

Title: Chapter 15 Question 34

34. Fast axonal transport is powered by

Feedback: Subhead: Axonal Transport

Learning Objective: Explain how slow axonal transport differs from fast axonal transport.

Bloom’s Level: 2. Understanding

a. kinesin and cytoplasmic dynein motors.

b. diffusion.

c. cilial beating.

d. electrical currents.

e. all of the above.

Type: multiple choice question

Title: Chapter 15 Question 35

35. When organelles such as mitochondria and vesicles bind to microtubules to travel toward axon terminals, they move at a rate

Feedback: Subhead: Axonal Transport

Learning Objective: Explain how slow axonal transport differs from fast axonal transport.

Bloom’s Level: 2. Understanding

a. substantially slower than the background movement of cytoplasm.

b. about the same as the background movement of cytoplasm.

c. substantially faster than the background movement of cytoplasm.

d. substantially slower than transport to the cell body.

e. substantially faster than transport to the cell body.

Type: multiple choice question

Title: Chapter 15 Question 36

36. Anterograde axonal transport is powered by _______ while retrograde transport is powered by _______.

Feedback: Subhead: Axonal Transport

Learning Objective: Explain how slow axonal transport differs from fast axonal transport.

Bloom’s Level: 1. Remembering

a. myosins; kinesin

b. axoplasmic flow; myosins

c. kinesin; cytoplasmic dynein

d. microtubules; myosins

e. cytoplasmic dynein; axoplasmic flow

Type: multiple choice question

Title: Chapter 15 Question 37

37. Microtubules play an essential role in

Feedback: Subhead: Axonal Transport

Learning Objective: Describe the role of microtubules in axonal transport.

Bloom’s Level: 2. Understanding

a. removing neurotransmitter from the synaptic cleft.

b. packaging neurotransmitters in vesicles.

c. axoplasmic flow.

d. fast axonal transport.

e. slow axonal transport.

Type: multiple choice question

Title: Chapter 15 Question 38

38. The functional outcome of a common class of drugs, monoamine oxidase (MAO) inhibitors, is to

Feedback: Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 3. Applying

a. reduce the availability of neurotransmitters such as acetylcholine and ATP in the brain.

b. increase the availability of neurotransmitters such as dopamine and norepinephrine in the brain.

c. reduce the availability of neurotransmitters such as dopamine and norepinephrine in the brain.

d. increase the availability of neurotransmitters such as GABA and glycine in the brain.

e. reduce the availability of serotonin in the brain.

Type: multiple choice question

Title: Chapter 15 Question 39

39. The duration of ACh activity at postsynaptic receptor sites is limited by

Feedback: Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 2. Understanding

a. a high concentration of AChE in the synaptic cleft.

b. a high concentration of intracellular AChE in the presnaptic terminal.

c. a large number of reuptake receptors on the pre-synaptic membrane.

d. the proximity of glial cells that absorb the ACh .

e. the size of vesicles released from the presynaptic terminal.

Type: multiple choice question

Title: Chapter 15 Question 40

40. The action of peptide transmitters appears to be terminated primarily through

Feedback: Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 2. Understanding

a. enzymatic degradation.

b. synthesis into new molecules.

c. uptake into neighboring glial cells.

d. reuptake into the pre-synaptic terminals.

e. diffusion.

Type: multiple choice question

Title: Chapter 15 Question 41

41. Inhibition of acetylcholinesterase in the synaptic cleft of a neuromuscular junction results in a(n)

Feedback: Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Discuss why the prompt removal of transmitter is important for normal synaptic function.

Bloom’s Level: 2. Understanding

a. reduction in the ACh available at the postsynaptic receptor.

b. substantial increase in the duration of the postsynaptic potential.

c. increase in choline available for synthesis inside the neuron.

d. substantial reduction in the amplitude of the postsynaptic potential.

e. significant delay in the latency of the postsynaptic response.

Type: essay/short answer question

Title: Chapter 15 Question 42

42. Describe two differences between the synthesis and packaging of peptides compared to low-molecular-weight neurotransmitters.

Feedback: One difference is that neuropeptides are synthesized primarily in the cell body rather than in the cytoplasm (often axon terminals). This leads to a second difference, which is that neuropeptides are then packaged into large dense-core vesicles in order to be transported to the release sites, while low-weight transmitters are packaged into smaller vesicles at the release site.

Subhead: Neurotransmitter Synthesis

Learning Objective: Explain how low-molecular-weight transmitters and neuropeptides differ in their synthesis, storage, and release

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 43

43. Given what you know about the synthesis of acetylcholine, name two ingredients that could be added to a neuron in order to increase acetylcholine availability in the cell.

Feedback: You could provide more of the two main ingredients needed for synthesis, choline and AcCOA. With these two precursors, more acetylcholine can be synthesized.

Subhead: Neurotransmitter Synthesis

Learning Objective. Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 44

44. Predict what would happen if you experimentally increase levels of GAD in a brain slice preparation.

Feedback: GAD, or glutamic acid decarboxylase, is an enzyme used to synthesize GABA from glutamate. If I were to experimentally increase GAD levels, I would expect to see an increase in GABA, and subsequently an increase in inhibitory transmission.

Subhead: Neurotransmitter Synthesis

Learning Objective. Explain how the synthesis of acetylcholine and other low-molecular-weight transmitters is controlled to meet the demands of release.

Bloom’s Level: 3. Applying

Type: essay/short answer question

Title: Chapter 15 Question 45

45. Give one example of feedback inhibition in the synthesis of neurotransmitters, and explain why the example illustrates this effect.

Feedback: One example of feedback inhibition is in the synthesis of GABA. GABA is synthesized from glutamate by the enzyme GAD. In some crustacean neurons, GABA levels have been shown to inhibit GAD activity, which illustrates the idea of feedback inhibition; as more GABA accumulates, less GABA is synthesized.

Subhead: Neurotransmitter Synthesis

Learning Objective: Explain the concept of feedback inhibition and give an example of a transmitter whose synthesis is regulated by this mechanism.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 46

46. Give one example of long-term regulation of neurotransmitter synthesis.

Feedback: One example is the effect of stress on the synthesis of norepinephrine. Prolonged activation of sympathetic neurons due to stress leads to an increase in the production of enzyme molecules used to produce norepinephrine. Because the production of these enzymes is based on activity levels of the neurons, it stimulates higher levels of norepinephrine production at times when more norepinephrine is being released.

Subhead: Neurotransmitter Synthesis

Learning Objective. Describe the difference between short-term and long-term regulation of transmitter synthesis

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 47

47. Why is it that only a small quantity of a peptide is needed to produce activity in a target cell?

Feedback: First, very low concentrations of peptides can still bind to target receptors, and peptides are not rapidly removed from the extracellular space by enzymes or through reuptake. Additionally, many peptides bind to metabotropic receptors which amplify the signal.

Subhead: Neurotransmitter Synthesis

Learning Objective: Explain why only a few molecules of a peptide are needed to influence a target cell.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 48

48. Some of the proteins that are responsible for packaging neurotransmitters into vesicles bind to more type of molecule. Give an example of an effect of this nonspecificity.

Feedback: One example of this nonspecificity is VIAAT, which is the transporter for both glycine and GABA. Because it binds to both, this results in both neurotransmitters being stored together in the same vesicles, and provides an example of co-transmission when the vesicles are released.

Subhead: Storage of Transmitters in Vesicles

Learning Objective: Explain the concept of co-storage and co-release.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 49

49. What is one way in which synaptic plasticity could be accomplished through co-transmission?

Feedback: Sometimes more than one neurotransmitter is released from a vesicle or synaptic terminal, labeled “co-transmission.” The proportion of each neurotransmitter that is stored or released will influence the effect on the receptor site. These proportions may be altered through development or experience, reflecting a version of synaptic plasticity.

Subhead: Storage of Transmitters in Vesicles

Learning Objective. Explain the concept of co-storage and co-release.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 50

50. What is the difference between anterograde transport and retrograde transport, and what do the two have in common?

Feedback: These two forms of axonal transport differ because one (anterograde) refers to transport toward the axon terminals, while the other (retrograde) refers to transport back to the cell body. Anterograde transport is powered by kinesin motors, while retrograde transport is powered by cytoplasmic dynein. They have in common a reliance on a microtubule structure that the motors can bind to and move the vesicles in the right direction.

Subhead: Axonal Transport

Learning Objective. Distinguish between anterograde transport and retrograde transport.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 51

51. Describe a major difference between slow axonal transport and fast axonal transport.

Feedback: In slow axonal transport, structural proteins flow along with cytoplasm away from the cell body, toward the axon terminals, at a rate of only a few mm/day. In fast transport, organelles bind to microtubules that run between the cell body and axon terminals. Movement can occur in both directions, and energy is used in order to power mechanochemical engines that drive the movement.

Subhead: Axonal Transport

Learning Objective: Explain how slow axonal transport differs from fast axonal transport.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 52

52. What are three mechanisms used to remove transmitter from the synaptic cleft?

Feedback: The three mechanisms include diffusion through the extracellular space, degradation of the neurotransmitter by enzymes, or reuptake of the transmitter into glial or neural cells.

Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 1. Remembering

Type: essay/short answer question

Title: Chapter 15 Question 53

53. Imagine that you are a scientist working to develop a drug that will increase acetylcholine signaling – specifically, your plan is to make more acetylcholine available at post-synaptic receptor sites. Based on your knowledge of neurotransmitter synthesis, storage, and degradation, provide one target mechanism that you could use to accomplish this goal.

Feedback: One way to ensure that more acetylcholine is available at target receptors is to reduce the amount of ACh that is removed from the synapse prior to reaching its target. An AChE inhibitor would prevent ACh from being broken down in the synapse, and result in a stronger ACh signal at the receptor site.

Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 6. Creating

Type: essay/short answer question

Title: Chapter 15 Question 54

54. Given what you know about how the actions of neurotransmitters can be terminated, give two examples of how the effects of norepinephrine could be reduced at a synaptic receptor.

Feedback: Two ways that a neurotransmitter can be silenced are through reuptake and through enzymatic degradation. So, in order to dampen the effects of norepinephrine, we could facilitate reuptake and/or introduce more enzyme (such as MAO) to help break down the norepinephrine.

Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 3. Applying

Type: essay/short answer question

Title: Chapter 15 Question 55

55. Give two examples of how the synthesis, transport, and/or inactivation of peptides differs from that of typical low molecular weight neurotransmitters.

Feedback: One example is that peptides are usually inactivated by diffusion, with no apparent mechanism for reuptake. A second example is that unlike low molecular weight transmitters, peptides are usually synthesized in the cell body and stored in dense core vesicles, rather than being created and stored in the synaptic terminal.

Subhead: Removal of Transmitters from the Synaptic Cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 15 Question 56

56. What is the mechanism by which ATP and ACh are most often inactivated?

Feedback: Both of these are usually inactivated by hydrolysis, accomplished by enzymes located on or near synaptic sites, or in the case of ATP, in glial cells.

Subhead: Removal of transmitters from the synaptic cleft

Learning Objective. Describe three mechanisms that remove transmitter from the synaptic cleft.

Bloom’s Level: 2. Understanding